Added Dig_By_Water group --> the water dig and remove the node but drop (if the item drop)

mods/default/functions.lua

@@ -96,6 +96,25 @@ grow_reeds = function(pos, node)
 end
 
 -- ABMs
+minetest.register_abm({
+	nodenames = {"group:dig_by_water"},
+	neighbors = {"group:water"},
+	interval = 1,
+	chance = 1,
+	action = function(pos)
+		local originalpos = pos
+		for dx=-1,1 do
+			for dy=-1,1 do
+				pos.x = pos.x+dx
+				pos.y = pos.y+dy
+				if minetest.env:get_node(pos).name == "group:water" then
+					minetest.env:set_node(pos, {name="default:air"})
+				end
+			end
+		end
+	end,
+})
+
 minetest.register_abm({
 	nodenames = {"default:cactus"},
 	neighbors = {"group:sand"},

mods/default/nodes.lua

@@ -623,7 +623,7 @@ minetest.register_node("default:junglegrass", {
 	buildable_to = true,
 	is_ground_content = true,
 	stack_max = 64,
-	groups = {snappy=3,flammable=2,attached_node=1},
+	groups = {snappy=3,flammable=2,attached_node=1,dig_by_water=1},
 	sounds = default.node_sound_leaves_defaults(),
 	selection_box = {
 		type = "fixed",
@@ -1678,7 +1678,7 @@ minetest.register_node("default:grass", {
 	walkable = false,
 	buildable_to = true,
 	is_ground_content = true,
-	groups = {snappy=3,flammable=3,attached_node=1,dig_immediate=3},
+	groups = {snappy=3,flammable=3,attached_node=1,dig_immediate=3,dig_by_water=1},
 	sounds = default.node_sound_leaves_defaults(),
 	after_dig_node = function(pos, oldnode, oldmetadata, user)
 	local item = user:get_wielded_item()
@@ -1735,24 +1735,24 @@ minetest.register_node("default:sponge", {
 			on_water = true
 		end
 		for i=-1,1 do
-			p = {x=pos.x+i, y=pos.y, z=pos.z}
+			local p = {x=pos.x+i, y=pos.y, z=pos.z}
-			n = minetest.env:get_node(p)
+			local n = minetest.env:get_node(p)
 			-- On verifie si il y a de l'eau
 			if (n.name=="default:water_flowing") or (n.name == "default:water_source") then
 				on_water = true
 			end
 		end
 		for i=-1,1 do
-			p = {x=pos.x, y=pos.y+i, z=pos.z}
+			local p = {x=pos.x, y=pos.y+i, z=pos.z}
-			n = minetest.env:get_node(p)
+			local n = minetest.env:get_node(p)
 			-- On verifie si il y a de l'eau
 			if (n.name=="default:water_flowing") or (n.name == "default:water_source") then
 				on_water = true
 			end
 		end
 		for i=-1,1 do
-			p = {x=pos.x, y=pos.y, z=pos.z+i}
+			local p = {x=pos.x, y=pos.y, z=pos.z+i}
-			n = minetest.env:get_node(p)
+			local n = minetest.env:get_node(p)
 			-- On verifie si il y a de l'eau
 			if (n.name=="default:water_flowing") or (n.name == "default:water_source") then
 				on_water = true
@@ -1774,8 +1774,8 @@ minetest.register_node("default:sponge", {
 					end
 				end
 			end
-			p = {x=pos.x, y=pos.y, z=pos.z}
+			local p = {x=pos.x, y=pos.y, z=pos.z}
-			n = minetest.env:get_node(p)
+			local n = minetest.env:get_node(p)
 			if change == true then
 				minetest.env:add_node(pointed_thing.above, {name = "default:sponge_wet"})	
 			else